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Write-error on swap-device crashed AC68U

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RocketJSquirrel

Senior Member
I got hundreds of these messages prior to a crash. I have never seen this before. Running Merlin 386.9 on my trusty old AC68U. And I do mean "old".
Jan 30 03:24:22 kernel: Write-error on swap-device (8:1:6401688)
Jan 30 03:24:22 kernel: Write-error on swap-device (8:1:6370784)
Jan 30 03:24:22 kernel: Write-error on swap-device (8:1:6456216)
Jan 30 03:24:22 kernel: Write-error on swap-device (8:1:6373320)
May 4 22:05:02 kernel: klogd started: BusyBox v1.25.1 (2023-01-06 15:03:02 EST)

I have been swapping to a USB stick in the router for years, and this is new. What does it mean?
 
It most likely means you need a new USB stick.
That seems probable.

It's been so long since I've had to look at this (68U has been humming along trouble free for years) that I can't remember where to look for swapping settings/activity/capacity. Could someone remind me? I kind of thought the router didn't really need to swap, that this was a kind of emergency outlet when memory filled but wouldn't actually get used. I'm not running any extra packages, just the bare bones Merlin firmware.
 
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That seems probable.

It's been so long since I've had to look at this (68U has been humming along trouble free for years) that I can't remember where to look for swapping settings/activity/capacity. Could someone remind me? I kind of thought the router didn't really need to swap, that this was a kind of emergency outlet when memory filled but wouldn't actually get used. I'm not running any extra packages, just the bare bones Merlin firmware.
Look back in the log for the first error messages not the last. It's possible that your USB drive became unmounted or there were other disk errors. In either case unmount the filesystem and repair it. If you enable the dc option in amtm it will attempt to do this automatically when your router boots up.
 
If you heavily use swapping, then a USB stick is a bad device to use for swapping. You'd be better off with a small SSD or HDD, as most USB sticks have very low write endurance.
 
Thanks for the replies. I pulled the USB stick and will see how the router works without it. I don't think I really need to swap, I probably just plugged in the stick because it was sitting around unused. It's a 1 GB stick, try to find one that small nowadays!
 

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